“The ecumenical vision of the patriarch is very helpful for me because we have some tendencies in the dialogue to avoid the theological questions and to handle other questions,” Cardinal Kurt Koch told CNA Oct. 22.

“His holiness, the patriarch, helped me to sustain that we have (the need) for theological dialogue between the Orthodox Church and the Catholic Church, (and) in this sense I think this visit can deepen our relationships,” he observed.

Cardinal Koch, who serves as the current president of the Pontifical Council for Promoting Christian Unity, made his comments the day after the Vatican’s release of Pope Francis’ official itinerary for the trip.

The trip will take place Nov. 28-30, and falls just days after Pope Francis’ Nov. 25 address to the European Parliament in Strasbourg.

It will take place largely in response to an invitation sent to Pope Francis by Patriarch Bartolomew I of Constantinople, asking him to participate in the celebration of the feast of St. Andrew, patron of the Orthodox world.

While relations between Catholic and Orthodox Churches are already on good terms, the cardinal explained that the Pope’s trip will be an opportunity to take these relations further through dialogue on theological points of diversion.

“It’s a very difficult dialogue because now we are discussing the theme of primacy within the Church and above all the primacy of the bishop of Rome,” Cardinal Koch observed, noting that due to historical divisions, the process of unity is “a very big challenge.”

He also emphasized the importance of dialoging with Muslims, saying that although continuous Catholic-Orthodox dialogue is needed, Islam is an especially crucial topic of discussion for the Church today.

For constructive dialogue to occur, the cardinal explained that moderate Muslims must make a clear distinction between themselves and extremist groups in order to help Christians and other persecuted minorities in today’s contentious times.

“I think it’s very, very important not to damage the dialogue with Muslims, but they must confess where they stand, and above all I think it’s very important to have the common message that violence is not the sister of religion.”

“The sister of religion is holy peace,” he said, noting that this is a message clearly and strongly promoted by Benedict XVI during his pontificate, which continues with Pope Francis.

“We have the experience of what St. John Paul II mentioned, the ecumenism of martyrdom, because all of the churches, the Orthodox Churches, the Evangelical Churches, the Catholic Churches in the Middle East have martyrs,” Cardinal Koch explained.

He drew attention to how the Church often refers to the blood of the martyrs as the seed which gives life to new Christians, and voiced his hope that the blood of the many modern day martyrs will be “the seed of the new unity between Christians.”

Prior to the announcement of his visit to Turkey, Pope Francis and Bartholomew I had already met numerous times. They issued a joint declaration during the Pope’s voyage to the Holy Land in May, and worked together in organizing an Invocation for Peace in the Middle East held at the Vatican Gardens June 8.

Bartholomew I has also been committed to organizing a pan-Orthodox synod, set to take place in 2016, in an attempt to transcend divisions between Orthodox Churches and to move towards an internal unity in favor of dialogue with Rome.

The close relation between Pope Francis and the Ecumenical Orthodox Patriarch have sparked rumors that they are collaborating on the Pope’s anticipated encyclical on ecology, making it a joint encyclical letter on the topic.